Electromagnetic device



F. E. wooD ELECTROMAGNETIC DEVICE Filed Nov. 21, 1931 Patented Aug. 22, 1933 ELECTROMAGNETIC DEVICE Frederic E. Wood, Hinsdale, Ill., assignor to Associated Electric Laboratories, Inc., Chicago, 111111., a Corporation of Delaware Application November 21, 1931 Serial No. 576,529

'3 Claims. (Cl. 2008Z) This invention relates in general to electromagnetic devices, but more particularly to electromagnetic relays such as are used as circuit breakers for high tension circuits, and the principal object of the invention is concerned with the provision of supporting and adjusting means of the circuit breakers in relays of this type.

A particular type of electromagnetic circuit breaker which is coming into more common useage, due to the many advantages it possesses, is a type wherein a pair of contacts carrying high tension current are mounted in a sealed glass tube containing a high degree of evacuation. The actuation of these contacts is brought about through the action of a glass rod acting as a lever which makes use of the elastic property of the glass to cause a mechanical actuation of the contacts in the glass tube. Corroding and arcing of the contacts is thereby prevented. Considerable difficulty has been encountered in devising means for mounting or supporting the evacuated glass tube due to its fragile and delicate nature since it must be supported so that the means, either manually or electromagnetically operated for actuating the rod, does not injure the device. Accordingly, it is an object of the invention to design suitable supporting and mounting means for a glass tube containing a circuit breaker of the nature described.

Another object of the invention is to devise suitable adjusting means for positioning the glass tube and rod with respect to its actuating device so that the proper adjustment of the contacts of the circuit breaker is brought about.

Other objects of the invention are concerned with the provision of suitable brackets or mounting plates for supporting one or more glass tubes or containers on various types of relays.

The invention is described in connection with the attached sheet ofdrawing which shows the preferred embodiment of the invention. Referring to the drawing; Fig. 1 shows a top viewof an alternating current operated electromagnetic device having a single glass tube and circuit breaker supported thereon; Fig. 2 shows a side view of the same device, while Fig. 3 shows a perspective view of a bracket arrangement and supporting assembly for .the glass circult breaker; Fig. 4 shows a top view of a direct current operated electromagnetic device employing a pair of glass circuit breakers supported by means of a bracket on the heel piece; Fig. 5 discloses a perspective view of the supporting and mounting arrangement for the circuit breaker shown inFig. 4; while Fig. 6 shows another perspective view of thebracket arrangement of Fig. 4. 7

Referring to the modification shown in Figs. 1, 2, and 3, this electromagnetic device is of the type which is suitable 'for operation with alternating current. A device of this nature is disclosed in more detail in a co-pending application of John Erickson, Serial No. 538,058, filed May 18, 1931, which became Patent No. 1,883,773 on Oct. 18, 1932. A circuit breaker of the type shown in the drawing in which the contacts are enclosed evacuation is disclosed in the August 8, 1931, issue of Telephony Magazine, page 42, and need not further be described. The electromagnetic de- .vice disclosed in Fig. 4 is an ordinary direct current relay such as is well known in the telephone art.

In Fig. 1 the electromagnetic device shown is such that, due to the nature of its construction as pointed out in the aforementioned pending application, it is adapted to be operated with alternating current. It comprises'a coil 1 having a winding wound thereon which is supported on a U-shaped laminated core 2. The armature 3 is suitably supported andpivoted opposite one end and one leg of the core.2 onto the bracket arrangement 4 so that the air gap may be suitably varied. The armature 3 has an arm carrying an insulated bushing 5 for actuating the circuit breaker as will be pointed out. A flat metal heel piece 6 is supported on'the laminated core 2 on one side thereof, andforms a support for the bracket 7 which is attached to the heel piece 6 by means 0! screws 8. A pair of relatively flexible discontinuous metal bands 9 and 10 are supported by screws 12 and 13 onto the lower turned up end of the bracket '7. A flat metal strip 11 clamps the metal bands 9 and10 by the screws 12 and 13 direct onto the bracket "7. Thebands 9 and 10 have openings, through which the screws 12 and 13 pass, which are in the form of slots as shown at 14 so that. these bands may be adjusted up or down to slightly vary the longitudinal position of the sealed glass tube-l5 which is supported on either end by the metal bands 9 and 10. The. bands it will be seen only partially encircle the tube 15, leaving a slight gap where they aresupported, so that a certain amount of flexibility is imparted to them. The glass tube 15 contains sealed therein under. a high degree of vacuum, a pair of contacts 16 which are actuated by the glass stem 17 projecting from the tube 15 and which is normally tensioned against thebushing 5 of the armature 3 by the tension spring 18 so as to in a sealed glass tube containing a high degree of maintain the stem in a normal position. The

tension spring 18 is suitably insulated and supported as by screws 19 onto an extension of the bracket '7.

With the construction shown and described it is seen that longitudinal movement of the tube either screws 12 and 13 and moving themetal bands 9 and 10 up or down will move the glass tube 15 at a slight inclination from its horizontal position so that a further variation of the opening of the contacts may be effected after the screws 12 and 13 are tightened.

As shown in the drawing, the contacts 16 are normally closed and upon actuation of the armature 3 a movement of the end of the stem 17 is effected and this in turn by means of the elastic properties of the glass tube moves the opposite end of the stem 17 against movable contacts 16 to open them. When it is desired to have the contacts in a normally opened instead of closed position, it is merely necessary to rotate the tube 15 one-hundred and eighty degrees about its axis inside of the metal bands 9 and 10, and after this is done it is necessary to loosen the screws 12 and 13 and move the metal bands 9 and-10 either up or down with-respect to eachv other in the. slots 14 and also increase the tension of the restoring spring 18 to normally hold the contacts open.

When the armature 3 is then operated the contacts will assume a closed position instead of open. 7

In the modification shown in Fig. 4, an ordinary direct current type of telephone relay is dis'-" closed having a form of counting bracket which is adapted to support a pair of glass tubes. This bracket 23 is supported on the flat heel piece 6' of 'the relay 1' at points 25 on the front and 26 on the rear of the bracket by means of screws. The relatively. flexible metal bands 19 and 20 are supported on one turned up edge of the bracket 23, while the metal bands 21 and 22 are supported on the opposite turned up edge of the bracket 23. These metal bands are clamped together in pairs by means of the metal strips 28 and 29 and secured to the plate 23 by screws. Each of the metal bands 19,20, 21, and 22 have a slot, similar to slot- 14 shown in Fig. 3, so that-they may be shifted up or down to move the glassztubes 15 and 15 for the purpose pointed out hereinbefore.

upwardly projecting extension 24 of the bracket 23 supports a pair of spring members 27 and 30 suitably insulated from the support 24 so that these spring members project above each of their'respective glass tubes 15 and 15 toengage the ends of the stems such as 17' and hold the stems against the armature bushings 5'.

With the form of construction of the bracket I shown in Figs. 5 and 6 a pair of glass tubes having in which the contacts are normally opened. With the adjustment provided due to the slots in the metal bands for holdingthe glass tubes, together with the longitudinal movement of the tube which 5 is permitted due to the flexibility of the metal bands, a wide variation of adjustment, and

has been designed, and it is seen that any slight modification apparent to those skilled in the art may be incorporated in the particular arrangement disclosed. What is thought to be novel and desired to be protected by Letters Patent is pointed out in the following claims.

What is claimed is:

1. In an electromagnetic device having an armature and a circuit breaker of the type mounted within an evacuated glass container, a bracket mounted on said device, a stem on said glass container for actuating said circuit breaker at one end and having the other end in operative relation to the armature so asto be actuated thereby, an extension on said bracket having means supported thereon for actuating said stem in opposition to the armature to restore said circuit breaker to normal position after said armature has actuated the stem, 2. pair of flexible bands encircling said glass container at spaced intervals, and adjustable means for mounting said metal bands on said bracket so as to vary the circling said glass tube to support the same, a

stem in said glass tube for actuating the circuit breaker and having one end in operative relation to the armature, said metal bands permitting the longitudinal movement of said glass tube so as to move said stem toward the armature and vary the extent of movement of the stem with I ment may be imparted to the tube, a fulcrumed stem in said vessel having one end in operative engagement with the armature and the opposite end controlling the pair of contacts, the longitudinal movement of said glass tube varying the fulcrum of said stem with respect to the armature and the contacts, and means comprising a slot. in each of said metal bands for supporting the same on said bracket and for adjustably varying the position of either one of said bands in a direction at right angles to said longitudinal movement of the glass tube to still further adjust the relationship of the stem with respectto the armature and the contacts.

4. In an electromagnetic device having an armature and a pair of contacts, said contacts mounted in a sealed glass tube and actuated by the armature through the mediumof a contact carrying flexible portion of said tube, a bracket supported on saiddevice and having an extension thereon projecting above said glass tube,

having one end thereof a pair, of flexible metal bands partially encircling said glass tube and holding the tube in fixed relation to said device, said glass tube arranged in one position to normally maintain said pair of contacts closed and in another position normally maintain the contacts open, means on said bracket extension for restoring the contacts to either normal postion after actuation by the armature, and means for adiustably supporting said metal bands on said bracket to accommodate the heel piece in operative relation to of said magnet heel piece and.

the core of said magnet and the other end thereof in operative relation with the tubular extension 01 the circuit switching device.

6. In combination with a circuit switching device comprising a sealed vessel to! vitreous elastic material within which is enclosed a pair or switching contacts operable by .an elongated tubular extension formed of a continuation of the material from which the vessel proper is 'made, a magnet having a heel-piece, a bracket arrangement holding the vessel in fixed relation to said heel-piece; and an armature, arranged to be operated by said magnet, fixed to said heel-piece inoperative relation said switching device.

'7. In a combination of in the preceding claim, characterized in that, the bracket arrangement is arranged to support a plurality of such switching devices. while the armature is arranged with'as many arms as there are tubular members.

'the character specified EREDERIC E. WOOD.

to the tubular member-o! 

